Converting Gas generators to Run On Propane?

[BSVLY]

Costco has a good deal on a 7500 KW Gen with a Honda Gas Engine that looks worth picking up. I need propane though. Has anyone converted a gas gen to propane? I see that there are kits to convert them over. Are these reliable once converted? Any cons/surprises?

Guessing it would void the warranty too. Just looking for some direct knowledge on these conversions. Thanks

 

[schmism]

yes they can be converted

yes there are kits

all you have to do is replace the standard gas carb with a propane regulator.

(quick google search)

Small Engine Generator Conversion Kit - Propane Conversion Kits - Natural Gas Conversion Kits

 

[Bird]

I have not done it myself, but yes, it's fairly common. When we bought a new 32' fifth-wheel RV, I had the dealer install a 4.5Kw Kohler generator, converted to propane. Everything I'd seen in the RV magazines indicated that you lose about 10-11% in the conversion, so that still left us with over 4Kw, more power than we ever needed.

 

[dk8019]

I've done it before on a 5.5kW unit I own, it's setup to run on NG, propane or gasoline, with now change to switch it between either. Very handy during an extended power outage, as I have 750 gallons of propane on tap. They also run quite a bit cleaner, the proof is in the 50 hour oil changes typicallly the oil on gas comes out fairly black and dark looking, on propane or NG, it barely darkens from the original state.

 

[BSVLY]

Thanks All... Yes the clean way to do it is modify a spare carb.. Good to know the conversions work. May go that way..

 

[firedog]

I converted both my gens to propane. (a 5500W & 10KW) A venturi device attaches to your existing carb. The 5500 was pretty straight forward, the 10KW lincoln was a little tougher. The kits ran about $200-250 and included venturi, regulator & hoses.

Generator Conversion Kits to Propane and Natural Gas.

 

[fiveacrefarmer]

I see that this thread is a few months old... maybe I can help regardless. I just converted my 5kw Coleman generator to propane. The process is as simple as can be. I ran the propane first through a two stage pressure regulator, then through a flow control valve, and straight into the carbeurator where the needle normally protrudes. I haven't installed an ignition solenoid as yet, although it is in my future plans. Lemme know if you're still interested in this as a project and I'll give more details.

Fun project. Hearing that engine turn over on propane the first time was a real kick!

 

[teg]

...Lemme know if you're still interested in this as a project and I'll give more details...

Shoot yea... :thumbsup: it never hurts to document what you did with details!

 

[ray66v]

I would love to convert mine, but I am afraid losing HP will leave my generator underpowered.

I am already pushing it to the limit.

 

[fiveacrefarmer]

Ray,

I've heard mention of losing HP when converting to propane and I'm not nearly an expert enough to say one way or the other. I'd recommend upgrading to a larger generator if you're already near your maximum draw. It looks to me like generator's hold onto their resale value like Dick Cheney holds Haliburton stock... might be time to sell the old one and pick up a larger genny with a "bad carb" listing on Craigslist. It's better to do the type conversion I mentioned with a worn out old carb because it requires drilling out the needle port thus permanantly altering the carb and preventing it from ever working for gasoline again.

I'll try to get some pictures of what I did and post them when my wife's not looking. She's awful jealous of my projects... seems to think she deserves as much of my time as the garage does.

 

[Bird]

I've heard mention of losing HP when converting to propane and I'm not nearly an expert enough to say one way or the other.

Me, neither, personally.:laughing: But when I was a full time RVer and member of the Good Sam Club and read lots of RV material, I know those who actually were supposed to be experts said you'd lose 11%. So when we bought a new fifth-wheel and wanted a generator on LPG, I had a choice of a 4kw Onan or 4.5kw Kohler at the same price. I went with the Kohler figuring after the conversion I'd have about what the Onan had before converting.

 

[ray66v]

Ray,

I've heard mention of losing HP when converting to propane and I'm not nearly an expert enough to say one way or the other. I'd recommend upgrading to a larger generator if you're already near your maximum draw.

Obviously that is an option, but not one I will ever consider. I have almost nothing to gain.

I have a high end 5500 watt generator that I only use once or twice a year, for a few hours. It runs a list of things so long, no one believes me, when it list them all. The only thing I turn off for it, is my central air.

It would make no sense for me to spend a wad of money, (I don't have), to replace it with a big expensive one that can run on propane, in the off chance there will be another event that will require me to run it for more than a day or two continuously, (which is about how much gasoline I keep on hand), and be in a situation where I would not be able to buy, or acquire, any gasoline anywhere.

Even if that happens, I have a propane fireplace for emergency heat, and I never have a large amount of food that would be lost to a power failure. So, it would be far cheaper to take the hit.

If I thought I could spare the HP, and I don't, I would spend the money to convert mine to propane, so I wouldn't need to keep so much gasoline around. But that's as far as I will go.

 

[firedog]

I would love to convert mine, but I am afraid losing HP will leave my generator underpowered.

I am already pushing it to the limit.

I haven't noticed an appreciable loss in power with mine. Most of the "power numbers" that I've seen are comparing the straight up btu content of gasoline to propane, not the engine performance.
In a practical application the propane performs closer to 100% of its btu ability that gasoline does to its simply because of the inefficiency of a liquid fuel burning in a gas/vapor combustion engine.
Both of the kits that I installed allow me to run either gasoline or propane.

 

[ray66v]

I haven't noticed an appreciable loss in power with mine. Most of the "power numbers" that I've seen are comparing the straight up btu content of gasoline to propane, not the engine performance.
In a practical application the propane performs closer to 100% of its btu ability that gasoline does to its simply because of the inefficiency of a liquid fuel burning in a gas/vapor combustion engine.
Both of the kits that I installed allow me to run either gasoline or propane.

I appreciate your input on this.

If I can get more input from real world situations, I may convert it.